The advantages of insulating steam discharge tubes in steam dispersion systems is discussed in detail in, inter alia, US Patent Publication US 2008/0061455/Lundgreen et al. published Mar. 13, 2008 and wherein insulating the steam discharge tube with a covering of polyvinylidene fluoride (PDVF) is disclosed and which has been found effective in reducing condensate and heat gain.
Also well known in the HVAC field is the insulation of pipes and tubes employing a filler material and metal cladding around it with the filler material typically being fibrous or a foam based polymer. However, in HVAC applications, the insulation material is generally considered unsafe for plenum use as it either sheds material or outgases. Further, this type of material cannot be easily manipulated into small areas and to be effective, it must be of a minimum thickness and can result in an enlarged cross-sectional area which contributes to higher air flow drag.
An additional drawback associated with foam insulation when used in association with pipes and tubing is that it is susceptible to damage from handling and age, and can be subject to contamination.